I. Technical Field
The present invention relates to pneumatic tools such as reciprocating tools, e.g. a hand-held saw reciprocatively driven by compressed air, and pneumatic rotary tools, e.g. a hand-held grinding tool driven to oscillate by compressed air.
II. Description of the Related Art
There have heretofore been developed pneumatic tools having various structures (for example, see Japanese Examined Utility Model Application Publication No. Hei 4-2781 (JP '781) and U.S. Pat. No. 5,755,292 (U.S. '292)).
These conventional pneumatic tools suffer, however, from problems such as a complicated structure, a relatively heavy weight, and a high air consumption. Further, supply and discharge of compressed air may fail to be smoothly performed, resulting in an interference with the operation of the tool concerned.